Originally Posted by
YYCfasha
Although you are already airside you need to exit, re-clear security, confirm if you have any checked bags and then customs - it is redundant and the process is a total disaster. YYC blames CATSA, CATSA blames YYC.
All airports that offer Transborder pre-clearance connections require travelers to re-do security. The US has stricter security requirements. The checked bags check is cause the US won't clear travelers without their baggage information, and its something I've had to do even at YVR. The alternative is you having to re-claim your bags and dropping them off again.